How Does Wavelength Affect the Efficiency of Photocatalysts?
The efficiency of a photocatalyst is highly dependent on the wavelength of the incident light. For instance, TiO2 is a widely used photocatalyst that has a band gap of about 3.2 eV, corresponding to ultraviolet (UV) light. If the incident light has a wavelength longer than the UV range (e.g., visible light), it will not have enough energy to excite the electrons, making the photocatalyst ineffective. Conversely, if the wavelength is shorter (higher energy), it can lead to the generation of highly reactive species that enhance the catalytic process.
